超声辅助法研究姜黄素对牛血清白蛋白损伤的影响

摘要

The mechanism of curcumin quenching bovine serum albumin( BSA) was investigated by fluorescence methods, and by adding UV-Vis spectroscopy, the damage of bovine serum albumin( BSA) by curcumin under ultrasonic irradiation was investigated. The results showed that curcumin quenched the intrinsic fluorescence of BSA by a static process. The molecular structure of BSA was changed slightly by ultrasonic irradiation. The quenching process of BSA intrinsic fluorescence and the damage degree of BSA molecules by curcumin was enhanced under ultrasonic irradiation,which made the quenching constants increased. It maybe result from the generation of reactive substances which oxidized amino acid residues and the obstructed the molecular structure of BSA when curcumin was activated by ultrasonic irradiation. The extent of damage was aggravated with the increasing of irradiation time (0-5h)and curcumin concentration(0.25×l0-5mol · L-1).The findings provided guidance for curcumin,served as a new photo-sensitizer, applying in sound dynamics therapy( SDT).%运用荧光法研究了姜黄素对牛血清白蛋白(BSA)的荧光猝灭机理,并结合紫外可见光谱探讨了超声照射下姜黄素对BSA的损伤.结果表明,姜黄素对BSA的荧光属静态猝灭,超声作用对牛血清白蛋白的分子结构影响较小,促进了姜黄素对牛血清白蛋白内源荧光的猝灭作用,使猝灭常数增大,辅助姜黄素进一步损伤蛋白质.原因可能是超声波激活姜黄素产生活性物质,活性物质氧化BSA分子内的氨基酸残基,破坏BSA分子结构.姜黄素对牛血清白蛋白的损伤程度随照射时间(0～5h)和姜黄素浓度(0～2.5×10-5mol·L-1)的增大而增加.研究结果为姜黄素作为一种天然光敏剂用于声动力学(SDT)提供了指导意义.